In the history of China's manned space flights, this time we have most space science tasks. Among them, Tiangong-2 space lab will carry plants to space, so as to study how human can grow plants in space. Gavin Blackburn reports.

In the movie "the Martian", astronaut Mark Watney survives on the Red Planet by growing potatoes. But the process was difficult, and any carelessness could mean no harvest.

In reality, growing plants in space is even harder. In Tiangong-2, scientists have built a mini "greenhouse", with controlled temperature and light. Rice and mouse-ear cress will be grown.

Professor of Shanghai institutes for biological sciences, Zheng Huiqiong, said, "Before the launch of the Tiangong space tab, most of our experienments were short-term. Biological experiments in space were limited to 20 days. But it's quite hard, or even impossible for higher plants to finish a biological cycle. And we have never conducted a full seed-to-seed growth cycle experiment in space. China will conduct the first of these seed-to-seed experiements in space through Tiangong-2."

The higher plant incubators are divided into two parts: one that stays in space, and one for plants that will return to earth.  The one that stays in space has four units: two for rice, two for mouse-cress.  The plants will be grown under long-day or short-day conditions for comparison. This will be the first real-time experiment of this kind in one incubator.

Zheng said, "The components of the seeds will probably change when there's no gravity. So we will analyze the seeds brought back from space, and see what has changed, and the reasons behind such changes."

Three cameras will record the entire growth cycle. Two are visible light cameras, the other is a fluorescent camera, which is used to study the flowering gene.

"The reason plants produce flowers is something called the flowering gene in these plants. In previous experiments in space, the plants flowered later than on earth. In the space experiment this time, we will observe and research the relations between flowering and gravity," said Zheng.

Expectations are high. Scientists hope the experiments on board Tiangong-2 will yield new discoveries applicable to life on earth.